PHAZER TURBO HEAD SHIM

[APEXTYSON]

HAS ANYONE TRIED TO RUN MOUNTAIN LITE WITH MCX TURBO KIT WITH OUT THE HEAD SHIM IN PLACE. WOULD LIKE TO BRING BOTTOM END POWER BACK BEFORE BOOST COMES ONANY HELP WOULD BE GREAT.

 

[promod63]

We took the shim out and now it has much better throttle response. Before you could pin the throttle to the bar and all it would do is go ber ber ber ber!!! It made 161 hp on our dyno at 14 #s with the head shim (Had a h@ll of a time just getting it to spin the absorber with the shim.)and 161 at 13#'s with out the shim and now it has some ride ability. We are at 4400 ft. Here is the dyno pull after the shim removal. This is just what we have observed.

http://www.youtube.com/watch?v=NeCHC4lm-WY

 

[PwdrNut]

We have taken them out and don't install them in new kits as a general rule. But we ride above 10K and are only running 10psi on premium.
We have 1000s of miles with no issues with this set up.

 

[powder muncher]

We have one here with 2 head-gaskets instead of the shim, the difference is dramatic way better response and top end. However needs better fuel don't be fooled .

 

[aksteepndeep]

So 10 lbs no head shim, cool on premium pump gas?? I would like some bottom end back. That was the worst part of the install.
I assume you did NOT change cam timing with no shim? Thanks guys

 

[snowy1]

So 10 lbs no head shim, cool on premium pump gas?? I would like some bottom end back. That was the worst part of the install.
I assume you did NOT change cam timing with no shim? Thanks guys

pwdrnut, said he was above 10,000 ft. that makes a difference. I don,t know what elevation you are riding at but if its not high elevation you may need better fuel.

 

[PwdrNut]

We do not change the timing.
We also tried stacking head gaskets and didn't like the performance, although it was better than the shim.
Remember: we're riding 10,000' + That is how we can "get away" with this.

 

[rfabro]

Promod63, what fuels were you running during those tests?

 

[promod63]

Straight 110 race fuel on the dyno at 13#'s. Customer is going to turn the boost down to 10 and try 91 gas. At this altitude it shouldn't be a problem. Any sea level guys having the same problem of no throttle response?

 

[aksteepndeep]

I ride 0-5000ft in Alaska. The lag is there and if I could help it I would give up a few ponies. What is the word on 100ll av gas? I hear some running it. I would rather stick to 91 pump gas if possible. I was thinking of removing the shim, retarding the timing and running 10 lbs. Thanks guys

 

[gsxr]

I ran with the head shim , 1000 ft to 8000 ft ,
response was good , 15 lbs on premium.

 

[yel_low]

i have no problems at all with response, my exhaust is wrapped with bandage and i made some improvments to blow off valve connection.
i heared pressure bouncing from behind/turbo when i dropped throttle, so i made new connections under throttle bodies and connected it togehter with blow off valve. now i hear pressure being released in front off engine right away, and response is much better.

 

[aksteepndeep]

What BOV is that? Did it come with the MCX kit? Looks clean

 

[yel_low]

my BOV is located at the intercooler and is made of MCX, totally Aluminium, non recirculating. i have no picture sorry.

 

[powder muncher]

Everyone always talks about it is OK at altitude....
With al due respect that is bulls------ on a turbo sled.

10 psi of boost is 10 psi no mater what altitude you are at , that is why turbos work well at altitude. ( the turbo makes up for the thinner Air and takes you to what ever boost level you set it at ) All things correct it will make exactly the same amount of power at 10 000 feet or sea-level.

Just because super-charger or any normally aspirated 2 or 4 stroke loose power and runs richer( at altitude) = less change of detonation ETC does not make it the same on a turbo.